Patrick W. Goodwill

• Chief Technical Officer at Magnetic Insight, Inc.

This article presents a new robust model for image reconstruction in magnetic particle imaging (MPI) for single-axis drive field scans, which is based on the deconvolution of gridded harmonic data. Gridded harmonic data, used commonly in MPI, does not map to underlying iron density but rather to the iron density convolved with the harmonic point-sp...

Objective. Magnetic particle imaging (MPI) is an emerging tomographic ‘hot spot’ imaging modality with potential to visualize superparamagnetic iron oxide nanoparticle tracer distributions with high sensitivity and quantitative accuracy. MPI shares many similarities with positron emission tomography (PET), where the partial volume effect (PVE) can...

This article derives and implements a computational physics model for model-based image reconstruction in magnetic particle imaging (MPI) applications. To our knowledge, this is the first ever computationally tractable model-based image reconstruction in MPI, which is neither constructed from calibration or simulation experiments or limited to spec...

One of the hallmark advantages of magnetic particle imaging (MPI) is the linear relationship between MPI signal and the concentration of magnetic nanoparticles (MNPs), allowing absolute tracer quantification. However, intrinsic...

Clinical adoption of NK cell immunotherapy is underway for medulloblastoma and osteosarcoma, however there is currently little feedback on cell fate after administration. We propose magnetic particle imaging (MPI) may have applications for the quantitative detection of NK cells. Human-derived NK-92 cells were labeled by co-incubation with iron oxid...

Background Sentinel lymph node biopsy (SLNB) is an important cancer diagnostic-staging procedure. Conventional SLNB procedures with 99mTc radiotracers and scintigraphy are constrained by tracer half-life and in some cases insufficient image resolution. Here we explore an alternative magnetic (non-radioactive) image guided SLNB procedure. Purpose T...

Magnetic particle imaging (MPI) is an emerging modality that can address longstanding technological challenges encountered with magnetic particle hyperthermia (MPH) cancer therapy. MPI is a tracer technology compatible with MPH for which magnetic nanoparticles (MNPs) provide signal for MPI and heat for MPH. Identifying whether a specific MNP formul...

Magnetic particle hyperthermia (MPH) enables the direct heating of solid tumors with alternating magnetic fields (AMFs). One challenge with MPH is the unknown particle distribution in tissue after injection. Magnetic particle imaging (MPI) can measure the nanoparticle content and distribution in tissue after delivery. The objective of this study wa...

Sentinel Lymph Node (LN) biopsy involves the identification and surgical removal of the first LN(s) that drain from a primary tumor to evaluate for metastasis by histopathology [1]. For several tumor types, the standard of care is to manage the regional LN basin separately from the primary tumor. For head and neck cancer, melanoma, and complex brea...

Introduction Clinical adoption of NK cell immunotherapy is underway for medulloblastoma and osteosarcoma, however there is currently little feedback on cell fate after administration. We propose magnetic particle imaging (MPI) for the detection, localization, and quantification of VivoTrax-labeled NK cells. Methods Human-derived NK-92 cells were l...

Purpose Magnetic particle hyperthermia is an approved cancer treatment that harnesses thermal energy generated by magnetic nanoparticles when they are exposed to an alternating magnetic field (AMF). Thermal stress is either directly cytotoxic or increases the susceptibility of cancer cells to standard therapies, such as radiation. As with other the...

Magnetic Particle Imaging (MPI) directly detects superparamagnetic iron oxide (SPIO) labeled cells. We have used MPI to detect SPIO-labeled dendritic cells (DC) migrated to the popliteal lymph nodes (pLN) after injection into the hind footpads. However, in some cases the low pLN signal could not be resolved from nearby higher footpad signal where w...

Magnetic particle imaging (MPI) is a new tracer-based imaging modality that is useful in diagnosing various pathophysiology related to the vascular system and for sensitive tracking of cytotherapies. MPI uses nonradioactive and easily assimilated nanometer-sized iron oxide particles as tracers. MPI images the nonlinear Langevin behavior of the iron...

This paper reports a comprehensive investigation of a magnetic nanoparticle (MNP), named M55, which belongs to a class of innovative doped ferrite nanomaterials, characterized by a self-limiting temperature. M55 is obtained from M48, an MNP previously described by our group, by implementing an additional purification step in the synthesis. M55, aft...

MPI directly detects superparamagnetic iron oxides (SPIONs), which should enable precise, accurate, and linear quantification. However, selecting a region of interest (ROI) has strong effects on MPI quantification results. Ideally, ROI selection should be simple, user-independent, and widely applicable. In this work, we describe and compare four MP...

Magnetic nanomaterials that respond to clinical magnetic devices have significant potential as cancer nanotheranostics. The complexities of their physics, however, introduce challenges for these applications. Hyperthermia is a heat‐based cancer therapy that improves treatment outcomes and patient survival when controlled energy delivery is combined...

The scientific community has made great efforts in advancing magnetic hyperthermia for the last two decades after going through a sizeable research lapse from its establishment. All the progress made in various topics ranging from nanoparticle synthesis to biocompatibilization and in vivo testing have been seeking to push the forefront towards some...

Magnetic Particle Imaging (MPI) is a recently developed tracer-based, noninvasive diagnostic imaging modality. MPI uses the Langevin-based magnetization of superparamagnetic iron oxide nanoparticles, to generate signal and spatially encode an image. MPI technology was introduced in the seminal research publication by Gleich and Weiznecker. Hardware...

In this study, we evaluate the hyperthermia efficiency of polypropylene (PP) fibers with incorporated magnetic nanoparticles (MNP), which are used to develop inductive heatable stents in cancer therapy. Further, we investigate their depiction in magnetic particle imaging (MPI). We show that the intrinsic loss power (ILP) value depends on the MNP ag...

Introduction: The rapid growth of research into immuno-oncology research has fueled a need to be able to evaluate the efficacy of immunotherapies in a timely and comprehensive fashion. However, established non-invasive imaging approaches have been insufficient to meet all requirements. Magnetic Particle Imaging (MPI) is a novel tomographic molecula...

p>The success of cancer immunotherapy has driven the rapid growth of research into immuno-oncology, which in turn has fueled the need to be able to determine the location of a variety of immune cells in solid tumors and systemically over time. There is a strong association between response to the new checkpoint inhibitor treatments and the immune s...

Magnetic fluid hyperthermia (MFH) treatment makes use of a suspension of superparamagnetic iron oxide nanoparticles, administered systemically or locally, in combination with an externally applied alternating magnetic field, to ablate target tissue by generating heat through a process called induction. The heat generated above the mammalian eutherm...

Magnetic Particle Imaging (MPI) is a promising new tracer-based imaging modality. The steady-state, nonlinear magnetization physics most fundamental to MPI typically predicts improving resolution with increasing tracer magnetic core size. For larger tracers, and given typical excitation slew rates, this steady-state prediction is compromised by dyn...

Magnetic Particle Imaging (MPI), introduced at the beginning of the twenty-first century, is emerging as a promising diagnostic tool in addition to the current repertoire of medical imaging modalities. Using superparamagnetic iron oxide nanoparticles (SPIOs), that are available for clinical use, MPI produces high contrast and highly sensitive tomog...

Magnetic particle imaging (MPI) is an emerging ionizing radiation-free biomedical tracer imaging technique that directly images the intense magnetization of superparamagnetic iron oxide nanoparticles (SPIOs). MPI offers ideal image contrast because MPI shows zero signal from background tissues. Moreover, there is zero attenuation of the signal with...

Image guided treatment of cancer enables physicians to localize and treat tumors with great precision. Here, we present the first in vivo results showing that a new imaging modality, Magnetic Particle Imaging (MPI), can be combined with Magnetic Hyperthermia into a image-guided theranostic platform. MPI is a noninvasive 3D tomographic imaging metho...

Background: Islet transplantation (Tx) represents the most promising therapy to restore normoglycemia in type 1 diabetes (T1D) patients to date. As significant islet loss has been observed after the procedure, there is an urgent need for developing strategies for monitoring transplanted islet grafts. In this report we describe for the first time t...

Magnetic Particle Imaging (MPI), a molecular imaging modality that images biocompatible superparamagnetic iron oxide tracers, is well-suited for clinical angiography, in vivo cell tracking, cancer detection, and inflammation imaging. MPI is sensitive and quantitative to tracer concentration, with a positive contrast that is not attenuated or corrup...

Gastrointestinal (GI) bleeding causes more than 300,000 hospitalizations per year in the United States. Imaging plays a crucial role in accurately locating the source of the bleed for timely intervention. Magnetic Particle Imaging (MPI) is an emerging clinically translatable imaging modality that images superparamagnetic iron-oxide (SPIO) tracers w...

Molecular imaging has been instrumental for unraveling the mystery of biological processes and for diagnosing disease with more accuracy than ever before. The existing repertoire of molecular imaging techniques has been exceedingly fruitful for both preclinical applications and clinical diagnosis, but to date, no technique combines exquisite tracer...

Inductive sensor-based measurement techniques are useful for a wide range of biomedical applications. However, optimizing the noise performance of these sensors is challenging at broadband frequencies, owing to the frequency-dependent reactance of the sensor. In this work, we describe the fundamental limits of noise performance and bandwidth for th...

Magnetic particle imaging (MPI) is a new molecular imaging technique that directly images superparamagnetic tracers with high image contrast and sensitivity approaching nuclear medicine techniques—but without ionizing radiation. Since its inception, the MPI research field has quickly progressed in imaging theory, hardware, tracer design, and biomed...

Magnetic particle imaging (MPI) is a rapidly developing molecular and cellular imaging modality. Magnetic fluid hyperthermia (MFH) is a promising therapeutic approach where magnetic nanoparticles are used as a conduit for targeted energy deposition, such as in hyperthermia induction and drug delivery. The physics germane to and exploited by MPI and...

Magnetic Particle Imaging (MPI) is an emerging tracer-based medical imaging modality that images non-radioactive, kidney-safe superparamagnetic iron oxide (SPIO) tracers. MPI offers quantitative, high-contrast and high-SNR images, so MPI has exceptional promise for applications such as cell tracking, angiography, brain perfusion, cancer detection,...

Pulmonary embolism (PE), along with the closely related condition of deep vein thrombosis, affect an estimated 600,000 patients in the US per year. Untreated, PE carries a mortality rate of 30%. Because many patients experience mild or non-specific symptoms, imaging studies are necessary for definitive diagnosis of PE. Iodinated CT pulmonary angiog...

Emergency room visits due to traumatic brain injury (TBI) is common, but classifying the severity of the injury remains an open challenge. Some subjective methods such as the Glasgow Coma Scale attempt to classify traumatic brain injuries, as well as some imaging based modalities such as computed tomography and magnetic resonance imaging. However,...

Cancer remains one of the leading causes of death worldwide. Biomedical imaging plays a crucial role in all phases of cancer management. Physicians often need to choose the ideal diagnostic imaging modality for each clinical presentation based on complex trade-offs between spatial resolution, sensitivity, contrast, access, cost, and safety. Magneti...

Magnetic Particle Imaging (MPI) is a promising new tracer modality with zero attenuation deep in tissue, high contrast and sensitivity, and an excellent safety profile. However, the spatial resolution of MPI is limited to around 1 mm currently and urgently needs to be improved for clinical applications such as angiography and brain perfusion. Altho...

Magnetic particle imaging (MPI) is an emerging tomographic imaging technology that detects magnetic nanoparticle tracers by exploiting their non-linear magnetization properties. In order to predict the behavior of nanoparticles in an imager, it is possible to use a non-imaging MPI relaxometer or spectrometer to characterize the behavior of nanopart...

The development of magnetic particle imaging (MPI) has created a need for optimized magnetic nanoparticles. Magnetic particle relaxometry is an excellent tool for characterizing potential tracers for MPI. In this paper, we describe the design and construction of a high-throughput tabletop relaxometer that is able to make sensitive measurements of M...

Purpose: Magnetic particle imaging (MPI) is a new imaging technology that directly detects superparamagnetic iron oxide nanoparticles. The technique has potential medical applications in angiography, cell tracking, and cancer detection. In this paper, the authors explore how nanoparticle relaxation affects image resolution. Historically, researche...

Stem cell therapies have enormous potential for treating many debilitating diseases, including heart failure, stroke and traumatic brain injury. For maximal efficacy, these therapies require targeted cell delivery to specific tissues followed by successful cell engraftment. However, targeted delivery remains an open challenge. As one example, it is...

Superparamagnetic iron oxide (SPIO) nanoparticles with optimized and well-characterized properties are critical for Magnetic Particle Imaging (MPI). MPI is a novel in vivo imaging modality that promises to integrate the speed of X-ray CT, safety of MRI and sensitivity of PET. Since SPIOs are the source of MPI signal, both the core and surface prope...

Magnetic Particle Imaging (mpi) is an emerging imaging modality with exceptional promise for clinical applications in rapid angiography, cell therapy tracking, cancer imaging, and inflammation imaging. Recent publications have demonstrated quantitative mpi across rat sized fields of view with x-space reconstruction methods. Critical to any medical...

We demonstrate that Magnetic Particle Imaging (MPI) enables monitoring of cellular grafts with high contrast, sensitivity, and quantitativeness. MPI directly detects the intense magnetization of iron-oxide tracers using low-frequency magnetic fields. MPI is safe, noninvasive and offers superb sensitivity, with great promise for clinical translation...

Introduction Numerous perfusion imaging techniques have been developed based on nuclear medicine, MRI, CT, and ultrasound.1 A key enabler of perfusion imaging is the high contrast inherent to nuclear medicine, which sees only a tracer and does not see tissue. Magnetic Particle Imaging (MPI) is an emerging molecular imaging modality that, like nucle...

Magnetic Particle Imaging (MPI) is a novel non-invasive biomedical imaging modality that uses safe magnetite nanoparticles as tracers. Controlled synthesis of iron oxide nanoparticles (NPs) with tuned size-dependent magnetic relaxation properties is critical for the development of MPI. Additional functionalization of these NPs for other imaging mod...

Purpose: Medical imaging techniques such as magnetic resonance imaging and magnetic particle imaging (MPI) utilize time-varying magnetic fields that are subject to magnetostimulation limits, which often limit the speed of the imaging process. Various human-subject experiments have studied the amplitude and frequency dependence of these thresholds...

Magnetic Particle Imaging (mpi) is a promising new modality that images only a magnetic tracer, commonly super-paramagnetic iron oxide (spio) nanoparticles [1, 2]. During data acquisition information about the dc component of the native image is lost, and must be recovered using some a priori knowledge such as image continuity and positivity [3,4]....

An MPI spectrometer [1-3] measures the harmonics generated when a nonlinear SPIO is excited by a sinusoidal field. The harmonic peak spectrum allows for comparing SPIOs spatial resolution, since the harmonics are related to the modulation transfer function of the MPI imaging PSF [4-5]. It is also powerful to directly measure the point-spread functi...

Magnetic particle imaging (MPI) is a promising imaging technique for a variety of clinical and scientific applications ranging from angiography [1] to stem cell tracking [2] . The native 2D point spread function (PSF) presents two challenges: the PSF is anisotropic, and there is an obscuring image “haze” that reduces image contrast due to the long...

The sensitivity of Magnetic Particle Imaging (MPI), at fewer than 1000 detectable iron-labeled cells, is already comparable to imaging techniques like nuclear medicine [1-2]. However, the true physical sensitivity limits in MPI have not yet been achieved. Importantly, the preamplifier stage of an MPI receiver chain must be optimized to achieve low...

Previous work has explored the effects of nanoparticle relaxation from the system matrix and x-space reconstruction points of view [1-8]. Here we demonstrate how relaxation can be used to “colorize” an image based on relaxation mechanisms using x-space reconstruction [9] and a pixel-wise linear model.

The predominant imaging techniques used for preclinical research currently include optical imaging, magnetic resonance imaging (MRI), and nuclear medicine [1]. While these techniques have widespread pre-clinical adoption, they face challenges such as signal attenuation with tissue depth, lack of quantitativeness, radiation dose, and poor image cont...

MPI resolution and SNR are driven by the magnetic response of the iron oxide nanoparticles. Prior work has shown that magnetic nanoparticles respond differently to a wide range of excitation frequencies and amplitudes. Most prior work on MPI spectrometers and relaxometers have tuned the transmit coil at a single frequency. 1-3 In contrast, in this...

Real-time MPI [1] has the potential to serve as a noninvasive alternative to X-ray angiography. In order to achieve real time MPI, we must (a.) generate vector-drive field waveforms at a location governed in real time by the physician, (b.) acquire the MPI image data in real time, (c.) reconstruct the MPI images in real time. We have designed our M...

Developing tracers for MPI and related applications requires a thorough understanding of underlying relaxation processes. In X-Space MPI reconstruction, relaxation has a profound impact on the image through a decrease in SNR and direction-dependent blurring. To probe the relaxation of potential MPI tracers, Goodwill et al., have developed an X-Spac...

Magnetic Particle Imaging (MPI) shows promise for medical imaging, particularly in angiography of patients with chronic kidney disease. As the first biomedical imaging technique that truly depends on nanoscale materials properties, MPI requires highly optimized magnetic nanoparticle tracers to generate quality images. Until now, researchers have re...

Ultrasound is among the most widely used non-invasive imaging modalities in biomedicine, but plays a surprisingly small role in molecular imaging due to a lack of suitable molecular reporters on the nanoscale. Here, we introduce a new class of reporters for ultrasound based on genetically encoded gas nanostructures from microorganisms, including ba...

Abstract We experimentally demonstrate a 20-fold improvement in acquisition time in projection reconstruction (PR) magnetic particle imaging (MPI) relative to the state-of-the-art PR MPI imaging results. We achieve this acceleration in our imaging system by introducing an additional Helmholtz electromagnet pair, which creates a slow shift (focus) f...

For magnetic particle imaging (MPI), specific absorption rate (SAR) and more critically magnetostimulation (i.e., dB/dt) safety limits will determine the optimal scan parameters, such as the drive field strength and frequency. These parameters will impact the scanning speed, field-of-view (FOV) and signalto- noise ratio (SNR) in MPI. Understanding...

Magnetic Particle Imaging (MPI) is a promising tracer imaging modality that employs a kidney-safe contrast agent and does not use ionizing radiation. MPI already shows high contrast and sensitivity in small animal imaging, with great potential for many clinical applications, including angiography, cancer detection, inflammation imaging, and treatme...

We measured the relaxation times of PSFs acquired at a range of scanning rate, which was varied by changing the excitation field strength. As excitation scanning rate increased, measured relaxation times decreased (Figure 1b). This effect is likely due to the stronger magnetic torque acting on the particles. Relaxation field delays were calculated...

Parkinson's Disease (PD) is a degenerative disorder that causes the malfunction and death of neurons in the substantia nigra and afflicts hundreds of thousands of Americans. There is no known cure for PD. However, stem cell transplant therapy holds promise for reversing the effects of PD. Preclinically, the mouse model of stem cell therapy for PD i...

The point spread function (PSF) in MPI has been found to be the derivative of the Langevin function. This PSF has noticeably longer “tails” than a single Gaussian. These tails of the PSF manifest as baseline blurring, which significantly decreases contrast and “glare” in MPI. Here, we develop a robust post-processing method to equalize (similar to...

Here our large-angle physical model of the Langevin equation with magneto-viscous relaxation has been found to agree quite well with the results of a Monte Carlo simulation for dynamic particle behavior in a magnetic field. Furthermore, the magneto-viscous relaxation time constant predicted through this model has been shown to agree with experiment...

This prototype system has already produced high quality images with spatial resolutions very similar to the theoretically predicted resolution across mouse and rat sized FOVs. We have imaged both plastic and biological imaging phantoms, as well as ex vivo mice (not shown). Some early images are shown below in Fig. 1b-c. Imaging times are comparable...

Atherosclerosis, or the formation of plaques in the arterial wall, leads to cardiovascular disease, the number one cause of death in the United States. Atherosclerosis develops through multiple stages, which makes it a particularly difficult disease to detect. Markers of these different stages of plaque development have been discovered, however. Ou...

In this work,a method to achieve higher, more isotropic resolution for x-space MPI through analyzing various FFP trajectories and developing multidimensional transmit/receive hardware was presented. However, many parameters remain to be optimized for this technique, including the various tradeoffs between pFOV coverage, scanning speed, and resoluti...

For angiography, stem cell imaging, and cancer imaging, magnetic particle imaging (MPI) can replace conventional techniques due to its safety in vivo, exquisite image contrast, and high detection sensitivity. However, compared to the theoretical physical sensitivity limit of a MPI scanner with 1 mm3 resolution using image 17 nm iron oxide nanoparti...

The time-varying drive field in MPI is subject to magnetostimulation and specific absorption rate (SAR) limits. For frequencies up to 50 kHz, magnetostimulation is the dominant safety concern [1-2]. In this work, we investigate both the frequency and duration dependence of magnetostimulation limits for the drive field in MPI.

MPI stem cell imaging - sensitivity and linearity: 9 pelletized, labeled hESC-derived cell populations (Fig. 2A) with varying cell numbers were imaged successively in the FFL imager. Fig. 2B shows the maximum image intensity from each reconstructed cell pellet image as a function of cell number. When a linear fit was applied, we found a strong line...

Magnetic Particle Imaging (MPI) commonly utilizes a Field Free Point (FFP) magnetic field gradient to localize magnetic nanoparticles [1-2]. With the benefits of two orders of magnitude reduced acquisition time or one order of magnitude signal-to-noise ratio (SNR) improvement, a gradient called a Field Free Line (FFL), which localizes particles to...

Magnetic Particle Imaging (MPI) is a new tracer imaging modality that is gaining significant interest from NMR and MRI researchers. While the physics of MPI differ substantially from MRI, it employs hardware and imaging concepts that are familiar to MRI researchers, such as magnetic excitation and detection, pulse sequences, and relaxation effects....

We acquire the first experimental 3D tomographic images with Magnetic Particle Imaging (MPI) using projection reconstruction methodology, which is similar to algorithms employed in X-ray computed tomography. The primary advantage of projection reconstruction methods is an order of magnitude increase in SNR due to averaging. We first derive the poin...

Magnetic particle imaging (MPI) is a new imaging modality that non-invasively images the spatial distribution of superparamagnetic iron oxide nanoparticles (SPIOs). MPI has demonstrated high contrast and zero attenuation with depth, and MPI promises superior safety compared to current angiography methods, X-ray, CT, and MRI angiography. Nanoparticl...

One quarter of all iodinated contrast X-ray clinical imaging studies are now performed on Chronic Kidney Disease (CKD) patients. Unfortunately, the iodine contrast agent used in X-ray is often toxic to CKD patients' weak kidneys, leading to significant morbidity and mortality. Hence, we are pioneering a new medical imaging method, called Magnetic P...

The ability to measure blood velocities is critical for studying vascular development, physiology, and pathology. A key challenge is to quantify a wide range of blood velocities in vessels deep within living specimens with concurrent diffraction-limited resolution imaging of vascular cells. Two-photon laser scanning microscopy (TPLSM) has shown tre...

Analyses of in vivo capillary data by LS-PIV and SVD. A, Analyses of in vivo line-scan data using LS-PIV (blue line) demonstrating good agreement with SVD (red line), the gold standard, on capillary flow. In this example, cross-correlations for LS-PIV were conducted between every line-scan and its 5th neighboring scan. B, Plot of the difference in...

Example Line-scan Data and LS-PIV Matlab Implementation. (PDF)

Loss of RBC continuity in space-time data when high velocities are measured with line-scans. A, Schematic of line-scan data of slow to moderate RBC velocities. Each sequential line-scan appears beneath the previous one, with time advancing from top to bottom. RBCs appear as continuous diagonal streaks in the space-time image when RBC velocities are...

Performance of LS-PIV with high velocities and flow reversal. A, LS-PIV analysis of simulation line-scan data with velocity increasing to 800 mm/s. Actual particle velocity is represented by the blue line (SNR of infinity). Analysis was performed on data with an SNR of 8, within a 426 µm-long region of interest, and displayed as red dots. B, LS-PIV...

Cross-sectional flow profiles in control artery and AV shunt. A, RBC speed as a function of transverse position in a control artery. B, RBC speed as a function of transverse position in an AV shunt. Maximum, mean, and minimum RBC speeds were calculated from pulsatile velocities across 5 s scans. Five separate datasets were analyzed at each position...

Schematic of the two-photon laser scanning microscope. Images and line-scan data were obtained using a locally constructed TPLSM. 100 femtosecond, 80 MHz pulses were generated by a Titanium:Sapphire laser oscillator (Mai Tai HP; Newport Spectra-Physics) and passed through a dispersion compensator (DeepSee; Newport Spectra-Physics). Laser intensity...

Example of output of analysis running Matlab code for LS-PIV. Completed analysis with Matlab code depicts the raw data with time aligned along the x axis, a composite of the cross-correlations, and Gaussian-fitted displacements. Note that these results are reported in units of ‘pixels’ for both displacement and time, where the spatial and temporal...

Effects of noise on performance of LS-PIV and SVD. Analyses of simulation line-scan data using LS-PIV and previously published SVD. Data had increasing velocity and SNRs ranging from 0.33 to 8. Blue and red dots correspond to LS-PIV and SVD analysis, respectively. Analysis parameters were matched between LS-PIV and SVD using a 100 µm-long region of...

Projection magnetic particle imaging (MPI) can improve imaging speed by over 100-fold over traditional 3-D MPI. In this work, we derive the 2-D x-space signal equation, 2-D image equation, and introduce the concept of signal fading and resolution loss for a projection MPI imager. We then describe the design and construction of an x-space projection...